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  #31  
Old 03-27-2020, 08:48 AM
charles Tauber charles Tauber is offline
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Originally Posted by packocrayons View Post
I've found when dealing with a bit of runout (and planing into the runout), a higher angle plane tears out less. Scraper plane may have been an exaggeration.
Does the plane you use have an adjustable throat?

During a class on hand tools, Rob Cosman promised us students that "95%" of woods can be planed to a finished surface - no tear-out - using a hand plane. I didn't think so, based on my many years of (largely ignorant) experience, but went at the piece of wood I had that was full of reversing grain direction.

After a few strokes of the plane and lots of tear-out, he suggested I close the throat to nearly zero. I tried that, but still had tear-out on the piece of wood I was using. He came by and I said, "See it isn't working". He looked at the plane I was using and said, that that wasn't "nearly zero" throat closure and then adjusted it to the point that there was only the narrowest band of light visible between the blade and the throat. Used that way, it eliminated all of the tear-out. (Yes the plane was sharp, but sharp wasn't the key.)

In some woods, a higher bedding angle/bevel can help, but I've not found that to be necessary in very soft woods like spruce and cedar. Blade/bedding angle and throat size are just two among the variety of "tools" in the arsenal of hand planing.

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Of course, sharp is the most important
As my story illustrates, sharp is a prerequisite but not the most important factor.

Last edited by charles Tauber; 03-27-2020 at 08:57 AM.
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  #32  
Old 03-27-2020, 10:53 AM
packocrayons packocrayons is offline
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Originally Posted by charles Tauber View Post
Does the plane you use have an adjustable throat?

During a class on hand tools, Rob Cosman promised us students that "95%" of woods can be planed to a finished surface - no tear-out - using a hand plane. I didn't think so, based on my many years of (largely ignorant) experience, but went at the piece of wood I had that was full of reversing grain direction.

After a few strokes of the plane and lots of tear-out, he suggested I close the throat to nearly zero. I tried that, but still had tear-out on the piece of wood I was using. He came by and I said, "See it isn't working". He looked at the plane I was using and said, that that wasn't "nearly zero" throat closure and then adjusted it to the point that there was only the narrowest band of light visible between the blade and the throat. Used that way, it eliminated all of the tear-out. (Yes the plane was sharp, but sharp wasn't the key.)

In some woods, a higher bedding angle/bevel can help, but I've not found that to be necessary in very soft woods like spruce and cedar. Blade/bedding angle and throat size are just two among the variety of "tools" in the arsenal of hand planing.



As my story illustrates, sharp is a prerequisite but not the most important factor.
I rarely remember to close the throat. My main plane I use for thinning plates is an old 1908 stanley no5 - it requires moving the frog to adjust the throat, which can be cumbersome. I'll definitely keep it in mind next time I run into these issues.

A plane with a proper adjustable throat I adjust often - and I agree it definitely helps.
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  #33  
Old 03-27-2020, 01:08 PM
redir redir is offline
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Originally Posted by Neil K Walk View Post
Thanks! I kind of got the methodology with using a brick and measuring at where the X brace intersection but found precious little on what actual distances I was looking for. This guitar will have 1/4" bracing so I'm thinking that less than .3 would be safer.
The thickness of the bracing (assuming that is what you are talking about) is not really relevant. But the height of it is. If you have a book or some plans then you will be fine. Deflection testing starts to become valuable after about 5 guitars of each type, dred, OM, parlor and so on. So starting to collect it now is a good idea. Document it well and ALWAYS use the same method and tools to do it.

I also do braced top deflection as well.
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  #34  
Old 03-27-2020, 10:51 PM
Neil K Walk Neil K Walk is offline
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Thanks again for your advice so far, everyone! I did what you said to do Charles, and things went much smoother, like a hot knife through butter.



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  #35  
Old 03-28-2020, 12:29 PM
Neil K Walk Neil K Walk is offline
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The planing technique also provides some beautiful results on the sitka as there is not dust to cloud the grain. For a $20 "student" set of Sitka the silking of this top is striking. It's actually visually nicer than the top of my Larrivee OM-03R.



The top is REALLY thin though. The "low spot" is .077" thick!

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